Key Laboratory of Polymer Processing Engineering of Ministry of Education, Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China.
State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, China.
Int J Biol Macromol. 2024 Jun;269(Pt 2):132141. doi: 10.1016/j.ijbiomac.2024.132141. Epub 2024 May 7.
To enhance the flame retardancy and mechanical performance of PLA, a polyelectrolyte complex predicated on lignin was obtained by electrostatic mutual adsorption of ammonium polyphosphate (APP), polyethyleneimine (PEI), and copper ions as raw materials. The FT-IR spectra and EDX analysis confirmed the successful synthesis of a lignin-based flame retardant hybrid (APL-Cu) containing copper, phosphorus, and nitrogen elements. The combustion test results showed that the peak heat release rate and total heat release of the PLA composite containing 12 wt% APL-Cu were decreased by 15.1 % and 18.2 %, respectively, as compared to those of pure PLA. The char residue morphology observation revealed that the addition of APL-Cu could promote the formation of a highly dense and stable graphitized char layer, while TG-MS detected the emission of refractory gases such as ammonia gas, carbon dioxide, and water during combustion. The strong hydrogen bonding between APL-Cu and the PLA matrix kept the composite maintaining good strength and toughness. The tensile strength and impact strength of PLA/6APL-Cu increased by 4.73 % and 65.71 %, respectively, due to its high crystallinity and good interfacial compatibility. This work provides a feasible method to develop biobased flame retardant hybrids for PLA composites with better fire safety and improved mechanical properties.
为了提高 PLA 的阻燃性和机械性能，以木质素为原料，通过静电相互吸附法制备了一种基于聚电解质复合物的阻燃剂，其中包括磷酸铵（APP）、聚乙烯亚胺（PEI）和铜离子。FT-IR 光谱和 EDX 分析证实了成功合成了含有铜、磷和氮元素的木质素基阻燃剂杂化物（APL-Cu）。燃烧测试结果表明，与纯 PLA 相比，添加 12wt%APL-Cu 的 PLA 复合材料的峰值放热率和总放热率分别降低了 15.1%和 18.2%。炭残留形貌观察表明，APL-Cu 的添加可以促进高度致密和稳定的石墨化炭层的形成，而 TG-MS 在燃烧过程中检测到氨气、二氧化碳和水等难燃气体的排放。APL-Cu 与 PLA 基体之间的强氢键使复合材料保持良好的强度和韧性。由于 PLA/6APL-Cu 的高结晶度和良好的界面相容性，其拉伸强度和冲击强度分别提高了 4.73%和 65.71%。这项工作为开发具有更好防火安全性和改善机械性能的 PLA 复合材料的生物基阻燃剂杂化物提供了一种可行的方法。
